Switch device and lens-fitted photo film unit

Abstract

A lens-fitted photo film unit includes a front cover which covers an outside of a main body. A flash light source is secured to the main body. A sliding mechanism for switching is kept slidable on the main body, for generating a signal to actuate the flash light source. A button projection is formed to project from the sliding mechanism, and positioned externally through an opening of the front cover. A positioning projection is formed on an inside of the front cover, has an engaging surface oriented crosswise to a sliding direction of the sliding mechanism. A lock arm is disposed on the sliding mechanism, has a contact surface for engagement with the engaging surface, to lock the sliding mechanism. When the button projection is pressed toward the main body, the sliding mechanism is deformed flexibly, and unlocked by disengagement of the lock arm.

1 . A switch device, including an operation projection disposed to project through an outer cover for covering a main body having a light source, said operation projection being slid to turn on and off a power source of said light source, said switch device comprising:
 a sliding mechanism, having a front surface where said operation projection is formed, and having a flexible support panel of which two lateral edges are set on a front surface of said main body in a slidable manner, there being a space between said support panel and said main body behind said operation projection, said support panel being movable between on and off positions with said operation projection inside said outer cover;   a switch, disposed on said main body, for turning off said power source when said sliding mechanism is in said off position, and for turning on said power source when said sliding mechanism is shifted to said on position from said off position;   a positioning projection, disposed to project from an inner surface of said outer cover toward said sliding mechanism, and having an engaging face oriented crosswise to moving of said sliding mechanism;   a lock portion, formed on said support panel, and having a contact surface for contacting said engaging face when said sliding mechanism is in said off position, to prevent said sliding mechanism from moving toward said on position;   wherein when said operation projection is pressed toward said main body while said sliding mechanism is in said off position, said support panel flexes toward said main body to shift said lock position toward said main body, and said sliding mechanism is allowed to move to said on position by disengagement of said contact face from said engaging face.   
   
   
       2 . A switch device as defined in  claim 1 , wherein said positioning projection has a second engaging face formed in a position in a sliding direction of said sliding mechanism, and oriented opposite from said engaging face;
 said lock portion has a second contact face for contacting said second engaging face;   while said sliding mechanism is in said on position, said support panel in pressing said operation projection toward said main body flexes toward said main body, to shift said lock portion toward said main body, to allow said sliding mechanism to move to said off position by disengaging said second contact face from said second engaging face.   
   
   
       3 . A switch device as defined in  claim 2 , further comprising a flexible lock arm, having a proximal end formed on said support panel, disposed to extend in said sliding direction, and having a distal end where said lock portion is formed. 
   
   
       4 . A switch device as defined in  claim 3 , wherein a slot is formed in said support panel, and said lock arm projects from one end of said slot and extends along said slot. 
   
   
       5 . A switch device as defined in  claim 1 , further comprising a light source circuit for charging power for said light source, wherein said switch turns on and off said light source circuit. 
   
   
       6 . A lens-fitted photo film unit including a main body, an outer cover for covering said main body, a light source secured to said main body, and an operation projection disposed to project through said outer cover, and slid to turn on and off a power source of said light source, said lens-fitted photo film unit comprising:
 a sliding mechanism, having a front surface where said operation projection is formed, and having a flexible support panel of which two lateral edges are set on a front surface of said main body in a slidable manner, there being a space between said support panel and said main body behind said operation projection, said support panel being movable between on and off positions with said operation projection inside said outer cover;   a switch, disposed on said main body, for turning off said power source when said sliding mechanism is in said off position, and for turning on said power source when said sliding mechanism is shifted to said on position from said off position;   a positioning projection, disposed to project from an inner surface of said outer cover toward said sliding mechanism, and having an engaging face oriented crosswise to moving of said sliding mechanism;   a lock portion, formed on said support panel, and having a contact surface for contacting said engaging face when said sliding mechanism is in said off position, to prevent said sliding mechanism from moving toward said on position;   wherein when said operation projection is pressed toward said main body while said sliding mechanism is in said off position, said support panel flexes toward said main body to shift said lock position toward said main body, and said sliding mechanism is allowed to move to said on position by disengagement of said contact face from said engaging face.   
   
   
       7 . A lens-fitted photo film unit as defined in  claim 6 , wherein said positioning projection has a second engaging face formed in a position in a sliding direction of said sliding mechanism, and oriented opposite from said engaging face;
 said lock portion has a second contact face for contacting said second engaging face;   while said sliding mechanism is in said on position, said support panel in pressing said operation projection toward said main body flexes toward said main body, to shift said lock portion toward said main body, to allow said sliding mechanism to move to said off position by disengaging said second contact face from said second engaging face.   
   
   
       8 . A lens-fitted photo film unit as defined in  claim 7 , further comprising a flexible lock arm, having a proximal end formed on said support panel, disposed to extend in said sliding direction, and having a distal end where said lock portion is formed. 
   
   
       9 . A lens-fitted photo film unit as defined in  claim 8 , wherein a slot is formed in said support panel, and said lock arm projects from one end of said slot and extends along said slot. 
   
   
       10 . A lens-fitted photo film unit as defined in  claim 6 , further comprising a light source circuit for charging power for said light source, wherein said switch turns on and off said light source circuit.